1 /* 2 * Virtio 9p backend 3 * 4 * Copyright IBM, Corp. 2010 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #include "hw/virtio/virtio.h" 15 #include "hw/virtio/virtio-9p.h" 16 #include "hw/i386/pc.h" 17 #include "qemu/sockets.h" 18 #include "virtio-9p.h" 19 #include "fsdev/qemu-fsdev.h" 20 #include "virtio-9p-xattr.h" 21 #include "virtio-9p-coth.h" 22 #include "hw/virtio/virtio-access.h" 23 24 static uint64_t virtio_9p_get_features(VirtIODevice *vdev, uint64_t features, 25 Error **errp) 26 { 27 virtio_add_feature(&features, VIRTIO_9P_MOUNT_TAG); 28 return features; 29 } 30 31 static void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config) 32 { 33 int len; 34 struct virtio_9p_config *cfg; 35 V9fsState *s = VIRTIO_9P(vdev); 36 37 len = strlen(s->tag); 38 cfg = g_malloc0(sizeof(struct virtio_9p_config) + len); 39 virtio_stw_p(vdev, &cfg->tag_len, len); 40 /* We don't copy the terminating null to config space */ 41 memcpy(cfg->tag, s->tag, len); 42 memcpy(config, cfg, s->config_size); 43 g_free(cfg); 44 } 45 46 static void virtio_9p_device_realize(DeviceState *dev, Error **errp) 47 { 48 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 49 V9fsState *s = VIRTIO_9P(dev); 50 int i, len; 51 struct stat stat; 52 FsDriverEntry *fse; 53 V9fsPath path; 54 55 virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, 56 sizeof(struct virtio_9p_config) + MAX_TAG_LEN); 57 58 /* initialize pdu allocator */ 59 QLIST_INIT(&s->free_list); 60 QLIST_INIT(&s->active_list); 61 for (i = 0; i < (MAX_REQ - 1); i++) { 62 QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next); 63 } 64 65 s->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output); 66 67 v9fs_path_init(&path); 68 69 fse = get_fsdev_fsentry(s->fsconf.fsdev_id); 70 71 if (!fse) { 72 /* We don't have a fsdev identified by fsdev_id */ 73 error_setg(errp, "Virtio-9p device couldn't find fsdev with the " 74 "id = %s", 75 s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL"); 76 goto out; 77 } 78 79 if (!s->fsconf.tag) { 80 /* we haven't specified a mount_tag */ 81 error_setg(errp, "fsdev with id %s needs mount_tag arguments", 82 s->fsconf.fsdev_id); 83 goto out; 84 } 85 86 s->ctx.export_flags = fse->export_flags; 87 s->ctx.fs_root = g_strdup(fse->path); 88 s->ctx.exops.get_st_gen = NULL; 89 len = strlen(s->fsconf.tag); 90 if (len > MAX_TAG_LEN - 1) { 91 error_setg(errp, "mount tag '%s' (%d bytes) is longer than " 92 "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1); 93 goto out; 94 } 95 96 s->tag = g_strdup(s->fsconf.tag); 97 s->ctx.uid = -1; 98 99 s->ops = fse->ops; 100 s->config_size = sizeof(struct virtio_9p_config) + len; 101 s->fid_list = NULL; 102 qemu_co_rwlock_init(&s->rename_lock); 103 104 if (s->ops->init(&s->ctx) < 0) { 105 error_setg(errp, "Virtio-9p Failed to initialize fs-driver with id:%s" 106 " and export path:%s", s->fsconf.fsdev_id, s->ctx.fs_root); 107 goto out; 108 } 109 if (v9fs_init_worker_threads() < 0) { 110 error_setg(errp, "worker thread initialization failed"); 111 goto out; 112 } 113 114 /* 115 * Check details of export path, We need to use fs driver 116 * call back to do that. Since we are in the init path, we don't 117 * use co-routines here. 118 */ 119 if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) { 120 error_setg(errp, 121 "error in converting name to path %s", strerror(errno)); 122 goto out; 123 } 124 if (s->ops->lstat(&s->ctx, &path, &stat)) { 125 error_setg(errp, "share path %s does not exist", fse->path); 126 goto out; 127 } else if (!S_ISDIR(stat.st_mode)) { 128 error_setg(errp, "share path %s is not a directory", fse->path); 129 goto out; 130 } 131 v9fs_path_free(&path); 132 133 return; 134 out: 135 g_free(s->ctx.fs_root); 136 g_free(s->tag); 137 virtio_cleanup(vdev); 138 v9fs_path_free(&path); 139 } 140 141 /* virtio-9p device */ 142 143 static Property virtio_9p_properties[] = { 144 DEFINE_PROP_STRING("mount_tag", V9fsState, fsconf.tag), 145 DEFINE_PROP_STRING("fsdev", V9fsState, fsconf.fsdev_id), 146 DEFINE_PROP_END_OF_LIST(), 147 }; 148 149 static void virtio_9p_class_init(ObjectClass *klass, void *data) 150 { 151 DeviceClass *dc = DEVICE_CLASS(klass); 152 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 153 154 dc->props = virtio_9p_properties; 155 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 156 vdc->realize = virtio_9p_device_realize; 157 vdc->get_features = virtio_9p_get_features; 158 vdc->get_config = virtio_9p_get_config; 159 } 160 161 static const TypeInfo virtio_device_info = { 162 .name = TYPE_VIRTIO_9P, 163 .parent = TYPE_VIRTIO_DEVICE, 164 .instance_size = sizeof(V9fsState), 165 .class_init = virtio_9p_class_init, 166 }; 167 168 static void virtio_9p_register_types(void) 169 { 170 type_register_static(&virtio_device_info); 171 } 172 173 type_init(virtio_9p_register_types) 174